There are realities in God that always remain invisible to us even if we enjoy their physical proximity. Angels, for example, have spirits as do we but do not have bodies as we do, therefore whether here or in heaven we have to believe they exist and are present even though we cannot detect them except through the power of faith.
There are, however, "unseen" things that are thus because they are happening at a place and a time different than the one we are inhabiting at any given moment. The Lord speaks of these kinds of things in the Gospel today when he excoriates with severity the religious leaders of his day who "performed religious works to be seen."
For the full text of the homily for the 31st Sunday in Ordinary Time visit Meeting Christ in the Liturgy by clicking here.